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rocky0
Jul 11, 2009, 07:38 AM
My well system is not preoviding water in a steady stream. It is pulsating. What do I do?

My water wel is not providing water in a steady stream. It pulxates. I have changed the pressure switch amd have lowered the small screw. Any other suggextions?

mazak
Jul 11, 2009, 09:48 AM
How much pressure is showing?

speedball1
Jul 11, 2009, 11:51 AM
You may find this interesting. Pulsation generally occurs when a liquid's motive force is generated by reciprocating or peristaltic positive displacement pumps. It is most commonly caused by the acceleration and deceleration of the pumped fluid. This uncontrolled energy appears as pressure spikes. Vibration is the visible example of pulsation and is the culprit that usually leads the way to component failure.

Unlike centrifugal pumps(which produce normally non-damaging high-frequency but low-amplitude pulses), the amplitude is the problem because it's the pressure spike. The peak, instantaneous pressure required to accelerate the liquid in the pipe line can be greater than ten (10) times the steady state flow pressure produced by a centrifugal pump. Damage to seals gauges, diaphragms , valves and joints in piping result from the pressure spikes created by the pulsating flow.

Remedy
Suggest that you install a pulsation dampener. Dampeners provide the most cost efficient and effective choice to prevent the damaging effects of pulsation. A surge suppressor is in design essentially the same as pulsation dampener. The difference primarily lies in sizing and pressurizing.

The most current pulsation dampener design is the hydro-pneumatic dampener, consisting of a pressure vessel containing a compressed gas, generally air or Nitrogen separated from the process liquid by a bladder or diaphragm. The dampener is installed as close as possible to the pump or quick closing valve and is charged to 85% of the liquid line pressure. Proper sizing of the pulsation or surge suppressor requires several calculations. A close contact with the suppressor's manufacturer will ensure the correct sizing for a particular application.

Conclusion
By knowing how to avoid situations that will create pulsations during the specification process, or while trouble shooting, you can eliminate a lot of problems, failed valves and equipment, and costly downtime.


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jlisenbe
Jul 11, 2009, 03:08 PM
I would look hard at the pressure tank. I would think it should act as a damper for any pulsing coming from the pump.

1. Where is the pump, above ground or in the well?
2. How old is the pressure tank?
3. Is your pressure gauge surging up and down with the surges in the water?
4. When water is being used, do you notice the switch cutting off/on every second or two? You can hear it click as the points close/open.